Tuesday, October 16, 2012

Your Vegetarian Child: How Healthy Are They? Are Their Nutritional Needs Being Met?

Concerned parents who want to raise healthy vegetarian children often ask about their children's specific nutritional requirements. Are they getting enough iron or calcium? Should they be taking supplements? Will they be as strong and grow as fast as their omnivorous friends? These are valid concerns, but all of them can be resolved if parents provide a balanced and varied diet. Of course, vegetarianism means different things to different people. At one end of the spectrum are vegans, who eat no animal products whatsoever. They exclude all foods associated with animals, including honey and gelatin. Then there are lacto-ovo vegetarians, who eat eggs and dairy products but no meat. Lactovegetarians eat dairy but not eggs or meat. At the other end of the spectrum are semivegetarians, who occasionally eat fish or fowl but no red meat and definitely emphasize a plant-based diet.

Vegetarian children are becoming more common as many parents choose vegetarianism in their search for alternative lifestyles. Parents, however, mustunderstand how to translate children's special nutritional needs into tonight's dinner. Vegetarians are often nutrition savvy and can provide a model of healthy eating, but there are different nutritional requirements for children and adults. Most important, children have higher metabolic rates and consequently higher energy requirements than adults.

Vegetarian diets are typically high in fiber, so children eating this diet, unlike their carnivorous counterparts, get sufficient fiber. [1] But bulky, fibrous foods can fill up small stomachs before enough calories are consumed. Recent studies confirm that sufficient calories may be a concern for preschool vegetarians, [2] so they need plenty of higher-calorie, nutrient-dense foods such as nut butters and dried fruit. studies from 15 and 20 years ago raised concerns that vegetarian children were shorter, [3] but a landmark study of a commune called "The Farm" in Summertown, Tenn., found that slightly slowed toddler growth completely normalized by age 10. [4] Children older than seven who follow a nutritious vegetarian diet can be expected to grow well--maybe even better than their omnivorous counterparts. [5,6]

Some nutrients are found predominantly in animal products, so vegetarians must make sure these nutrients are included in their diets, whether by careful food selection or supplementation. Prime among them is iron, which is required for making red blood cells. Vegetarian children do have fewer red blood cells than omnivores. [7,8] When levels are too low, theresult is anemia, which may cause learning and psychomotor problems, fatigue and infection. My observation is that vegetarian children whose basic diet consists of fast food, macaroni and cheese, instant noodle soups and pizza are often anemic. Vegetarian children in carnivorous households who eat only parts of the family meal often eat a high-starch diet that puts them at risk of anemia. I have noticed that children who eat beans or tofu several times a day and dark green vegetables along with a source of vitamin C at mealtime (to increase iron absorption) have plenty of red blood cells.

Despite the risk of lower iron levels affecting learning in young children, older vegetarian children may actually have higher IQs than carnivores. [9] Anemia is also caused by a vitamin B12 deficiency. Because vitamin B12 is found in all animal products, deficiency is of primary concern for vegans. B12 is stored in the body, so a deficiency can take several years to manifest. However, only dietary B12 is incorporated into breast milk, so it is important for breast-feeding vegans to get enough B12. The risk is a B12 deficiency in the baby, which can cause severe neurological damage. Because B12 is also found in bacteria, young children do get a bit from putting toys or objects in their mouths. A B12 deficiency in young vegan children can slow their growth. [10-12] Clearly vitamin B12 supplementation is in order for breast-feeding vegans, their babies and vegan children.

The high-fiber content of vegetarian diets also retains some minerals in the gut, reducing absorption of iron, zinc, iodine, calcium and selenium. [13] Phytates, the fibers found in whole wheat, are the worst offenders. A zinc deficiency is more critical in vegetarian children than in adults for two reasons. First, children need relatively more zinc per pound of body weight than adults. Second, adults can adapt to a diet low in zinc by absorbing a higher percentage of the mineral from their food, whereas children are unable to make this adjustment. Because lactovegetarians consume dairy products, a good source of zinc, they are usually not deficient in it. However, the main source of zinc in vegan diets is wheat, the same grain that inhibits its absorption. Insufficient zinc may reduce appetite and decrease resistance to infection. [14] Parents should make sure their vegan children eat nuts, seeds, legumes, whole grains and soyfoods in order to get enough zinc.

Calcium content is probably the most controversial aspect of vegan diets. While soy-based supplemental formulas and soy milks fortified with calcium can substitute for cow's milk, many children raised on dairy-free diets have low calcium intakes. In the past, calcium intake never concerned me--after all, we didn't evolve drinking milk past infancy--but I've seen too many dairy-free children with poor teeth or bone problems. Children who drink milk substitutes not fortified with calcium are at most risk. Vegan children should drink two cups of fortified soy or other milks daily and eat tofu made with calcium and other foods rich in calcium. Vitamin D, required to absorb calcium, is also added to some soy- and rice-milk substitutes. Vegan children in gloomy climates may not get enough sunshine to manufacture vitamin D. On rare occasions, dark-skinned young vegans even have rickets, a vitamin D deficiency disease, when they are breast-fed exclusively past six months or eat lots of whole wheat. [15,16] Breast milk alone doesn't provide enough vitamin D for darker-skinned toddlers, so if they don't get a couple hours of sunlight a week, a vitamin D supplement is suggested.

What about fats and oils? For their first two years, children need dietary cholesterol to form myelin nerve coatings. Breast milk is high in cholesterol. After age two, cholesterol requirements decline, and children can make all the cholesterol they need in their livers. Studies of school-age vegetarian and carnivorous children found they have the same cholesterol levels. [17] In general, vegetarian children have a higher ratio of polyunsaturated to saturated fatty acids in their diets. Their lower level of saturated fats could lead to healthier adulthoods. However, chocolate, butter and cheese are high in saturated fats, while crackers, pastries and deep-fried food may contain harmful trans fatty acids.

Making careful food choices in any vegetarian diet is still necessary to ensure children eat the optimal fats. DHA, docosahexaenoic acid, for example, is an omega-3 fatty acid found in breast milk, cold-water fish, plant sources such as flax or pumpkin seeds, and dark green vegetables such as kale or chard. DHA is important for fetal and infant brain development. [18] Although breast milk remains the primary source of DHA, researchers found significant variations in breast-milk DHA levels around the world. The lowest concentrations were found in vegan and American mothers, and the highest in mothers who ate fish regularly. [19] Plant-based DHA supplements are available, and vegans should consider them if their diets lack this essential fatty acid.

Parents may think raising a healthy vegetarian child requires a Ph.D. in nutrition, but they shouldn't feel daunted. Major problems are rare, usually affecting babies whose parents make up their own, inadequate infant formula using soy milk or other bases without providing additional nutrients. In fact, well-fed vegetarian children may actually be healthier because they escape contamination from hormones and other chemicals fed to food animals. Eating lower on the food chain means children accumulate fewer pesticides and other toxic organochlorines such as PCBs and dioxin. [20] These chemicals accumulate from birth in fat tissue, so healthy childhood diets can provide lifelong protection. Adult vegetarians with a healthy lifestyle have a 30 percent lower chance of dying prematurely, and most causes of adult death are long-term conditions that may actually begin in childhood. [21] Children who eat healthily from birth are instilled with intelligent eating habits--a skill that can mean a lifetime of good health.